The present invention relates to golf balls, such as one-piece golf balls, solid golf balls composed of a core enclosed by one or more cover layer, and thread-wound golf balls. The invention also relates to molds for molding such golf balls.
Horizontally separating two-part molds have hitherto been used as molds for injection molding a cover resin material over a core in the manufacture of golf balls. When such a two-part mold is used, a seam line corresponding to the parting line of the mold appears on the golf ball.
This seam line is convenient for visually inspecting the golf ball and for applying indicia to the ball. For example, flash normally forms at the seam line corresponding to the parting line of the two-part mold. By placing the ball in a buffing apparatus so that the seam line prior to deflashing is centrally positioned, buffing can be efficiently carried out. It is thus important to know where the seam line is located, and to position the ball accordingly.
When an indicia such as lettering, a design or a trade mark is applied onto the seam line of a golf ball, it is essential to know the position of the seam line beforehand.
However, to improve the aerodynamic properties and increase the distance of travel in recent golf balls, and to make the arrangement of dimples formed on the surface of the ball as dense and uniform as possible, it has become common practice to place a plurality of dimples across the parting line. This has made it impossible to clearly distinguish, as a belt, the seam line on the surface of the ball which is left when the ball is molded in a two-part mold and which corresponds to the parting line of the mold. As a result, in subsequent steps, it has been difficult to smoothly and efficiently carry out such operations as visual inspection of the golf ball and the application of indicia at specific positions.